Method of making a valve



Oct. 6, 1964 D. SINKLER METHOD OF MAKING A VALVE Original Filed Dec. 13.1956 5 Sheets-Sheet 1 INVENTOR.

Q BY 4; ATTORNEY Oct. 6, 1964 n. SINKLER 3,152,205

METHOD OF MAKING A VALVE Original Filed Dec. 13', 1956 5 Sheets-Sheet 2INVENTOR.

054$ SIN/(L El? ATTORNEY D. SINKLER METHOD OF MAKING A VALVE OriginalFiled Dec. 13. 1956 5 Sheets-Sheet 3 INVENTOR 0511s SIN/(LEI? ATTORNE?Oct. 6, 1964 n. SINKLER METHOD OF MAKING A VALVE Original Filed Dec. 13,1956 5 Sheets-Sheet 4 o Tg INVENTOR.

DEAS SIN/(LEI? ATTOZJ United States Patent 3,152,295 IVETHGD 0F MAKWG AVALVE Deas Sinkler, 5790 Mad River Road, Dayton 9, Ohio Originalapplication Dec. 13, 1956, Ser. No. 62%,839. Divided and thisappiication June 39, 1960, Ser. No. 42,459

Claims. (Cl. 264-249) This invention relates to valves, and moreparticularly to valves which have been designed to provide free turningor the valving member thereof. This is a division of application SerialNo. 628,039, filed December 13, 1956, and now forfeited.

An object of the invention is to produce a valve having ribs therein forareas characterized by high sealing pressures between the valving meansand valve body, said valve also having areas of reduced pressure.

Another object of the invention is to produce a valve with a sealingmember disposed between the valving member and body to reduce the torquerequired to turn or operate the valve.

A further object of the invention is to produce a valve having thehereinabove described characteristics, having cavities provided thereinto accommodate axial and radial expansion and contraction of the sealingmeans.

Still a further object of the invention is to produce a valve providedwith a sealing member interposed between the valving member and bodywherein high pressure sealing areas are established and maintained byexpansion and contraction of the sealing member against ribs provided inthe body or valving member.

Another object of the invention is to teach a method of utilizing asealing member or sleeve of orientable material, the physical propertiesof which are improved by the method of manufacture or fabrication.

A further object of the invention is to produce a valve having thehereinabove described characteristics in which the properties of thesealing member are improved in the areas surrounding the flow passagesthereof.

These and other objects are attained by the means described herein andas disclosed in the accompanying drawings, in which:

FIG. 1 is a top view of a valve embodying the teachings of the presentinvention.

FIG. 2 is a sectional view taken on line 22 of FIG. 1.

FIG. 3 is a view of FIG. 1 of the valve body, with the valving member,sealing member, diaphragm, cover and gland removed.

FIG. 4 is a sectional view on line 44 of FIG. 3.

FIG. 5 is a sectional view on line 5-5 of FIG. 4.

FIG. 6 is a sectional view taken on line 66 of FIG. 4.

FIG. 7 is a sectional view taken on line 7-7 of FIG. 4.

FIG. 8 is a section taken on line 8-8 of FIG. 4.

FIG. 9 is a sectional view taken through a pre-formed sealing member orsleeve of orientable material.

FIG. 10 is a sectional view on line 1fi-10 of FIG. 9.

FIG. 11 is a view similar to FIG. 9, showing the sleeve material afterhaving been cold coined, showing the direction of orientation andlamination of the material.

FIG. 12 is a section on line 1212 of FIG. 11.

FIG. 13 is an illustration of FIGS. 9 and 11 in superimposedrelationship for purposes of providing an understandable comparison oftheir relative sizes and shapes.

FIG. 14 is a section on line 1414 of FIG. 13.

FIG. 15 is a partial view of the valve body of FIG. 7, with the sleeveof FIGS. 11 and 12 initially inserted there- FIG. 16 is similar to FIG.15, illustrating the sleeve as having been expanded into place bysizing.

FIG. 17 is a greatly enlarged view of one of the ribs of FIG. 16 and thesleeve associated therewith, and illus- 3,152,205 Patented Oct. 6, 1964trating a high pressure area of greater orientation and an area ofreduced pressure and lesser orientation.

FIG. 18 is an enlarged diagrammatic view illustrating the approximatecrystalline structure of a preferred sleeve material.

FIG. 19 is an enlarged view showing the fibrous structure of thematerial of FIG. 18 in oriented condition.

FIG. 20 is a perspective view of a sleeve as it would appear in acompleted valve structure and showing its areas of maximum orientationand intermediate areas of lesser orientation.

FIG. 21 is a sectional view illustrating the manner in which a valve,embodying the teachings of the present invention, may be fabricated byapplying a moldable body material around a previously formed sleeve asin FIG. 20, and illustrating a construction which does not utilizecavities between portions of the sleeve and body, as illustrated in FIG.17.

With particular reference now to the drawings, the numeral 3% denotesgenerally a valve having a rotatable valving member. Said valve, as bestillustrated in FIG. 2, may comprise a body member 32 having flowpassages 34 therethrough and providing with a cylindrical or taperedbore denoted generally by the numeral 36 intersecting flow passages 34.The numeral 38 denotes generally a rotatable valving member which ispreferably though not necessarily frusto-conical, having flow passages49 therethrough which are adapted to be selectively aligned with flowpassages 34 of the body. Shank 42 projects upwardly from the valvingmember, being provided at its upper end with flats 44 to facilitate theattachment of an operating lever 46.

The numeral 55 denotes generally a sealing member or sleeve oforientable material interposed between the adjacent faces of the valvingmember 38 and bore 36 of the body. A sealing diaphragm 52 is interposedbetween body 32 and a cover 54 which is held in sealing relationshipwith the body by means of studs 56 and nuts 58, as illustrated. A gland6t) threadably engages cover 54 for providing axial adjustment of thevalving member while maintaining sealed relationship between thediaphragm and that member. It should be understood that the presentinvention is neither limited by nor directed to the specific structuraldetails of the sealing diaphragm, cover and gland 6@, said relationshipbeing exemplary rather than restrictive.

With particular reference now to FIGURES 4, 5 and 7, the numeral 62denotes continuous ribs which extend outwardly of and completelysurround flow passages 34; the numeral 64- and 64a denote continuousoutwardly projecting ribs located above and below said flow passages andwhich extend circumferentially of the bore in distinction to ribs 62which are disposed radially with respect to the fiow passages. Thenumerals 66 denote rib areas that are common to rib areas 62 and 64,whereas rib 66a is common to rib areas 62 and 64a. 68 and 68a denotevertical ribs to provide further locking of the sealing member or sleeve59 against rotation and to increase the stability of the assemblyagainst tipping of the valving member with respect to the body.

Projection 70 and 72 extend inwardly from the bore of the valve body andupward from the bottom of the bore of the valve body to provide locatingseats for the bottom of the sealing member, extending, however, onlypartially across the wall thickness of the sealing member.

The numerals 74 and 74a represent cavities disposed above rib 64 andbelow rib 64a, respectively; whereas the numeral 7 6 denotes a cavityintermediate ribs 62 which circumscribe the flow passages 34 andintermediate ribs 64 and 64a which circumscribe the bore above and belowthe fiow passages.

In the preferred embodiment of the invention the bore-adjacent ends offlow passages 34 of the body are provided with additional areas ofenlarged diameter which have been indicated by the numerals 7 3 in FIGS.4, 5, 7, 15, 16 and 17. It will be noted that the enlarged areas 78completely surround and circumscribe the intersection of the flowpassages 34 with bore 36 through the body, said areas 78 beingchamfered; by way of example.

According to the teachings of the present invention, sleeve 50 may befabricated from a rigid material such as Monel metal, copper, brass, andother sirnilar substances having inherent self-lubricating andanti-galling properties. The sleeves may likewise be fabricated fromresilient material such as rubber, by Way of example.

However, it is preferred that the sleeve be of a material that ischaracterized by having resilience and elasticity under certain conditius, yet being subject to deformation under load in order to produce astrengthening effect by cold work or orientation in the areas where suchstrengthening is desired. The material should also be characterized by alow coefficient of friction, also for purpose of applications involvingsolvents, and other chemicals it should be characterized by inertnessand resistance to corrosion. The sleeve material should likewise be suchas to permit it to be used over wide temperature and pressure ranges.

The preferred sleeve materials include those of the polyethylene group,particularly the halogenated ethylenes which are characterized byoutstanding resistance to corrosives and solvents and extremely lowcoefiicients of friction.

Polytetrafluoroethylene (Teflon) is such a desirable material. It is,however, characterized by a relatively high linear thermal coefficientof expansion. It is also subject to permanent deformation underconditions of excessive pressure. It is therefore desirable to provideareas such as 74-, 74a, 78 and 76 into which it can expand and contractwith changes of temperature and/or pressure.

The preferred construction illustrated in FIG. 4 providessimultaneously:

(:1) Locking of the sleeve in place with respect to the body.

(b) Areas of high sealing pressure 62, 64, 64a, 66 and 66a adjacent toand above and below the flow passages.

(c) Intermediate internal areas of substantially reduced pressure uponthe valving member 33, FIGS. 2 and 4, for minimizing the torque requiredto operate the valve.

(:1) Substantial cavities 74, 74a, 76 and 78 to accommodate expansionand contraction of the sleeve material minimizing the cold flow undersevere conditions.

(e) The establishment of sealing pressure in the rib areas 62, 64, 64a,66 and 66a by axial and radial contraction or expansion of the sleeveagainst the edges of said ribs upon cooling or heating.

Teflon is one of a number of plastic materials of the orienting type.Resistance to cold flow under pressure is materially increased by coldwork. Specifically the tensile strength in the direction of working thematerial within and beyond its elastic limits is a function of thereduction in cross section. These orienting types of materials also haveplastic memory. This means that a material, after having been deformed,has the tendency to return to its original shape.

These properties are utilized in the preferred construc tion of thisinvention. The Teflon sleeve 50, FIGS. 9 and 10, is initially formedconsiderably shorter and with a substantially larger outside diameterthan in its finished form. The sleeve is cured or sintered by heating to700 F. for three hours and allowed to cool. It is then cold formed as inFIGS. 11 and 12 to reduce its outside diameter and reduce itscross-sectional area by to 50% with a proportionate increase in length.In this condition it is so proportioned as to require substantialadditional reduction in section by press fitting into the valve body asillustrated in FIG. 15. Subsequent enlargement of the inner and outerdiameters is accomplished by means of a sizing plug. This operationcauses additional orientation in the rib areas Q, as illustrated inFIGS. 16 and 17, by further reducing the section in these areas byapproximately 25% This sizing operation also causes the intermediatearea R to expand into a locking relationship with the opposite sides ofthe ribs, 62, 64, 64a, 66, 66a, 68 and 63a. Such expansion, however,does not completely fill the expansion areas, as illustrated at 76 inFIGS. 15, 16 and 17, leaving sufficient room for expansion andcontraction of the sleeve into the expansion cavities 74, 74a, 76 and 78without completely filling them. Upon heating or cooling of theassembled valves, these locking areas of the sleeve further seal againstleakage by expanding or constracting against the edges of the ribs.

With reference now to FIG. 20, I have illustrated an oriented sleeve ofthe type which is found in a completed, operable valve structure, andfor clarity of detail and understanding the various mating areas of thesleeve have been designated by numerals 100 higher than the numeralsdesignating the mating parts of the valve member, as follows 162, 1nd,164a, 166, 166a, 168 and 168a denote areas of high compression Whichalso provide areas of a relatively high degree of orientation, whereasthe numerals 174-, 174a, 176 and the chamfered area 178 denote areas ofrelatively lesser orientation.

In order to more thoroughly describe the problem solved by my invention,the following dissertation on the characteristics of Teflon will behelpful:

Teflon is furnished as a dry flufly powder. It may be used pure or withfillers such as fiber glass which may be incorporated to improve itsnatural physical properties. The normal process for forming Teflon partsconsist of compressing the powder cold in metal dies. The part is thenremoved from the mold and is sintered at approximately 700 F. forvarying lengths of time depending on the mass and shape of the partbeing made. Upon removal from the furnace the hot sintered parts may beallowed to cool slowly to room temperature or may be quenched by rapidlycooling in water or some other suitable medium or may be hot coined inthe preform die. Parts allowed to cool slowly have a relatively coarsegrain, crystalline structure. Parts quenched have a much finer grainstructure. Parts hot coined in a cold metal die tend to be quenched onthe surface. Parts may be finished to accurate dimensions by eitherbeing hot coined and allowed to cool in the coining mold or they may becold coined. Sometimes during the coining operation it is desirable toreduce the parts in section by compression beyond the elastic limit ofthe part in order to improve the physical properties of the Teflon.

Teflon molded by compression tends to have a laminar structure. Theplanes of lamination occur perpendicular to the axis of the direction ofthe force of compaction. In unoriented molded pure Teflon, the tensilestrength in the direction of compaction is approximately 1500 p.s.i.,while the tensile strength to the direction of compaction isapproximately 3000 p.s.i.

Orienting or cold work of Teflon by compression beyond its elastic limitresults in the squashing and elongation of crystals into a fibrous typeof structure vastly increasing its tensile strength in the direction ofwork, i.e. it is strengthened transverse the direction of reduction insection. T ensile strength may be increased to as much as 15,000 p.s.i.by cold Work. Stiflness is also improved by cold work.

Teflon has plastic memory to its sintered uncoined shape. It may bedeformed by subsequent operations or by use within or beyond its elasticlimits and still be caused to return to its original sintered shape byresintering 700 F. It may also be caused to partially return to itsoriginal shape by heating to lower than sintering temperatures. Recoveryin slightly oriented (5 to 15% reduction in section) Teflon will startto occur above 450 F; Teflon with medium orientation (15 to 35%reduction) will start to recover between 300 F. and 450 F. Fullyorientated Teflon will have some recovery at any increase intemperature. The degree of recovery is a function of increase intemperature and/or the length of time the Teflon is exposed at a giventemperature.

Orientation of Teflon tends to reduce its linear thermal coefficient ofexapnsion in the direction of orientation upon heating and to increaseits linear thermal coefficient of expansion upon cooling.

In the present invention the properties obtained in molding, quenching,and cold working are all utilized and are necessary for the optimumoperation of the valves under different operating conditions.

In the drawings:

FIGS. 9 and 10 are sections through a preformed sleeve 50 for a 1"valve.

FIGS. 11 and 12 are sections through a cold coined sleeve for a 1" valveshowing the direction of orientation and lamination of the Teflon.

FIGS. 13 and 14 are sections of the preform and coined sleevessuperimposed to show the relative sizes and shapes. It is apparent thatthe plastic memory of the finished sleeve makes it want to recoverbecoming shorter and thicker and expanding in its OD. and LD.

FIG. 15 is a section of a 1 valve through the center line of the portswith the sleeve in place but not sized.

FIG. 16 is similar to FlG. 15, but with the sleeve expanded into placeby sizing.

FIG. 17 is an enlarged view of FIG. 16 showing rib details, locking ofthe sleeves and the remaining expansion cavity.

FIG. 18 is an enlarged view of the approximate crystalline structure ofnon-oriented Teflon.

FIG. 19 is an enlarged view showing the fibrous structure of orientedTeflon, G being the direction of reduction in section and H being thedirection of elongation of section.

In FIGS. 9 and 10 the preform is preferably made in a mold in which thecavity and force are both tapered to permit lateral compression of thepowders. This causes the part to be laminar radially from the centralaxis. Parts of pure Teflon are preformed at pressures of 1500 to 3000p.s.i. Parts of reinforced Teflon require pressures up to 15,000 p.s.i.or even greater in order to obtain non-porous parts of uniform density.The preferred tapers in the preform die for the present invention fallbetween 4 and 8 for the outer surface and between 2 and 6 on its innersurface. The relative taper between the two being held between 1 /2 and2 /2". Other relative tapers would be preferred for finished parts ofdifferent tapers.

After molding the preform is removed from the mold and is heated to 700F. for a period of three hours or longer and is then water quenched from700 F. to room temperature.

In FIGS. 11 and 12 the coined sleeve is preferably formed in a moldwhich reverses the tapers from the preform so as to obtain radialpressure on the sintered preform and to compensate for the inherentspring back so as to obta n a part which is cylindrical on the outsideand tapered 2 per side on its inner surface.

The coined sleeve preferably has an outer diameter approximately .050"larger than the bore of the valve body into which it will be placed. Theinner diameter is preferably the same size or slightly smaller diameterthan the plug to be used in the valve.

In FIG. 15 the sleeve is pressed into the body, thus reducing both itsinner and outer diameters, leaving ap proximately .063" clearancebetween the outer diameter of the sleeve and the relief areaintermediate of the sealing and locking ribs.

In FIGS. 16 and 17 the sleeve is shown after a sizing operationconsisting of forcing a tapered sizing plug, not illustrated, into thebore expanding the sleeve to partially fill the expansion cavity 76 andchamfer 78. This operation serves to further orient the sleeve in theareas Q,

between the ribs 62 and the plug 38. This operation also serves toexpand the sleeve into the chamfer 78, extending around the port 34 ofthe body, thus providing additional sealing around the port.

In order to properly describe how sleeves formed by the foregoingprocess supplement the rib expansion cavity construction in valves, itis necessary to describe in more detail the properties of pure andfilled Teflon and more particularly how these properties are aflected bymolding and cold working procedures.

There are many reasons why the use of pure Teflon is desirable over theuse of Teflon containing fillers. First of all it is chemically inertover a wide temperature range and has an extremely low coeflicient offriction. Un oriented pure Teflon, however, has a high thermalcoefficient of expansion and relatively poor resistance to cold flow.For example:

Pure Teflon permanently deforms under a static load at 122 F.approximately 4 to 8 percent at 1200 lbs. per square inch. Permanentdeformation at 2400 lbs. per square inch approximates 25 percent. Thisdeformation, however, does not increase unless the load or thetemperature increases. Thus a Teflon part that had been orientated by 25percent reduction at say 2400 lbs. per square inch could safely be usedup to that pressure without fear of further change in dimensions.

The use of fillers in molded Teflon is not new and serves to reduce thelinear thermal coefficient of expansion, to increase resistance to coldflow and to increase stiffness. Fillers, however, introduce some otherproperties and conditions which may not be desirable. First, they tendto increase the coefiicient of friction. Secondly they requireconsiderably higher molding pressure in order to produce densenon-porous preforms. Many are subject to chemical attack in service.Others such as carbon, graphite, copper powder and other similarconducting materials can cause electrolytic cell corrosion of matingmetal parts. In some cases the fillers themselves can actuallycontaminate the solution being handled, either by mechanically becomingunattached from the Teflon matrix or by chemical attack such as occursin the case of calcium fluoride in the presence of sulphuric acid. Thecalcium fluoride reacts with sulphuric acid to liberate hydro-fluoricacid into the solution. In the case of certain desirable fillers such asfiber glass the molding powders become much more fluffy, thus requiringa much larger loading chamber in the preform dies. For example:

Pure Teflon has a bulk factor of 4 to 1. This means that a loadingchamber of approximately three times the size of the finished piece.Teflon filled with 15 percent fiber glass, however, has a bulk factor ofapproximately 7 /2 to 1, therefore a loading chamber nearly twice thesize of that required for pure Teflon is necessary in the preform. Thisnot only makes the dies more expensive but also requires a longer strokeof the compressing force in order to accomplish the same results. Thissame glass filled Tefion powder also requires a compressive force of atleast 15,000 p.s.i., in order to obtain parts that are dense andnon-porous; thus in many cases a larger size press is required to obtainparts of the same dimensions as could be obtained on smaller presses inpure Teflon.

For the purposes of the present invention filled Teflon would be usedprimarily to reduce deformation under loan and to decrease the linearthermal coeflicient expansion of Teflon. The same results, however, maypractically be obtained by proper orientation of pure Teflon.

Sealing against leakage is a function of the unit pressure over theentire seal area. The torque required to turn a vmve is a function ofthe pressure exerted in the sealing area and its coefficient offriction. Pure Teflon has a low coeflicient of friction. It is wellknown that the addition of fillers substantially increases thecoefficient of friction, particularly under increasing loads.

For service at low pressures and low temperatures,

adequate sleeves can be made of pure Teflon with a minimum amount ofcold working. This would provide for valve requiring a minimum of torqueto operate and a minimum danger of corrosion or contamination of thesolution being handled. With unoriented Teflon sleeves, valves can bemade to satisfactorily handle pressures up to 150 lbs. per square inchand temperature swings in the order of 150 F.

Unoriented 15 percent glass filled Teflon sleeves extend the temperaturerange to approm'mately 200 F., however, sleeves of pure Teflon orientedby reduction of approximately '25 percent in section also performsatisfactorily in 200 temperature swings yet require considerably lesstorque to operate the valve than the glass filled sleeves.

The use of glass filled sleeves oriented by 25 percent reduction in areaextends the useful temperature range to approximately 250 F., however,pure Teflon sleeves oriented by approximately 50 percent reduction insection also handle this temperature range with considerably less torquerequired to turn the valve. Higher pressures and temperatures can behandled with filled and unfilled Teflon which have correspondinglyfurther reduction in section.

The following is a table of dimensions of a typical pure T eflon valvesleeve for a 1" valve for service alternating from 50 F. to 300 F. inthe varying stages of molding and insertion into the valve. Valvesconstructed with 15 percent fiber glass filled Teflon made by the sameprocedure would handle temperature swings from 50 F. to 350 F. but wouldrequire twice the number of foot pounds of torque to turn the plug.

A. Dimensions at Centerline of Sleeve From the foregoing, it will benoted that I have thus provided simple yet highly effective means forproviding a valve which will require a mim'mum of torque in order toeffect relative movement between the valving member and body member, andwherein means are provided intermediate or between the valving memberand bore of the body member for providing a leakproof fit eifectivethroughout wide variations in temperature, pressures and vacuums. Itwill be further noted that I have likewise utilized the means by whichhigh sealing pressures are effected around the fluid passageways of thevalve for positively securing and anchoring a sealing member in placerelative to the valving member and body.

It should also be noted that the sealing member in the structuredescribed may readily be removed and replaced in case of damage withoutthe necessity of expensive machining and lapping.

It should also be noted that the valve requires no lubricant or packing,thus minimizing the danger of contamination of the fluids being handled.

It should be understood that the present invention covers not only thestraight-way or two-port valve illustrated in FIG. 2 of the drawings,but any other type of multi-port valves.

It should likewise be understood that in certain instances it may bedesirable to secure the sleeve member to one or the other of the matingmembers, viz., the valving member or body member, or both of them, bymeans of welding or cementing. The invention likewise contemplates theuse of sealing members fabricated from materials having lower linearthermal coeflicients of expansion from that of the mating parts, as wellas material having higher linear thermal coeiiicients of expansion asdescribed herein.

It should likewise be understood that the present invention contemplatesa valve construction wherein the sealing member is secured to andcarried by the valving member as well as by the body member, asillustrated; and also wherein two sealing members would be utilized whenone or" the sealing members is secured to and carried by the valvingmember and the other mating sealing member is secured to and carried bythe body members.

With reference now to FIG. 21, it will be noted that the numeral 50denotes generally a sealing member formed substantially as illustratedin P16. 20, and wherein a body-member-forming substance has beenillustrated exteriorly thereof, being positively keyed or locked theretoas by means of ribs 64 and 64a; said body member being fabricated of amoldable material, such as, by way of example, but not of restriction,KEL-F (monochlorotritiuoroethylene), which moldable material might alsobe interposed between a metal body shell and the aforesaid sealingmember.

In conclusion, it will be noted that various changes and modificationsmay be made in the structural details of the devi e, within the scope ofappended claims, without departing from the spirit of the invention.

What is claimed is:

1. The method of providing selected areas of improved sealing propertiesand increased resistance to deformation under compressive load in anorientable, crystalline sealing member located between a valving memberand the bore of the body of a valve, wherein the bore is provided withcontinuous raised areas which circumscribe the boreadjacent-end of flowpassages in the body and with recessed areas adjacent said raised areas;which method comprises the steps of reducing the diameter of the sealingmember incident to inserting it in said bore while in a crystallinestate, and of then cold working it by increasing its internal diameterfor compressing it radially beyond its elastic limits over the raisedareas in the bore while simulta-' neously forcing other portions of thesealing member to partially fill at least a portion of the recessedareas of the bore for locking said member therein.

2. Method of claim 1 wherein areas of greater orientation are producedin the sealing member over the raised areas, and wherein areas of lesserorientation are produced in the sealing member over the recessed areas,said sealing member being further received in said recessed areasincident to expansion and contraction of the sealing member.

3. The method of providing selective areas of improved sealingproperties and increased resistance to deformation under compressiveload in an orientable, crystalline sealing member in the form of asleeve located between the valving member and the bore of the body of avalve, wherein the bore is provided with continuous raised areas whichcircumscribe the bore-adjacent-end of flow passages in the body and withrecessed areas adjacent said raised areas, and wherein the outsidediameter and thickness of the sleeve are initially greater than thefinal outside diameter and thickness of the sleeve; which methodcomprises the steps of initially compressing the sleeve while in acrystalline state for partially orienting it and reducing its dimensionsfor insertion into said bore, then cold working the sleeve by radiallyexpanding it in the bore for compressing it beyond its elastic limitsover the raised areas in the bore while simultaneously forcing otherportions of the sleeve to partially fill at least a portion of therecessed areas of the bore for locking the sleeve therein, whereby areasof improved sealing properties and in-' creased resistance todeformation are produced in the sleeve over said raised areas, andwherein areas of lesser orientation are produced in the sleeve over therecessed areas of the bore.

4. The method of producing selected areas of improved sealing propertiesand increased resistance to deformation under compressive load in anorientable, crystalline sealing member located between a valving memberand the bore of the body of a valve; which method comprises the steps ofproviding continuous raised areas in the bore which circumscribe thebore-adjacent-end of the flow passages in the body and which projectoutwardly from other areas of the bore toward the valving member,initially cold working the sealing member while in a crystalline stateby uniformly compressing it beyond its elastic limits for partiallyorienting it by reducing its section and elongating the crystalsthereof, introducing said partially oriented sealing member into thebore, and of further cold working it by expanding it in said bore forfurther compressing it beyond its elastic limits over the raised areasin the bore and of simultaneously forcing other portions of the sealingmember to fill at least a portion of the other areas of the bore forlocking the sleeve therein, wherein those portions of the sealing memberdisposed over the raised areas in the bore are characterized by improvedsealing properties and increased resistance to deformation undercompressive load.

5. In a method of producing a sleeved valve having a valving member, abody member and a sealing member therebetween, and wherein the bodymember includes a bore having continuous raised areas therein whichcircumscribe the bore-adjacent-end of the flow passages in the body andwhich project inwardly toward the valving member, the steps of providinga sealing member of orientable crystalline material having a crystallinestate and capable of reduction in section by working while in acrystalline state with sealing areas of greater reduction in sectionbetween those portions in contact with the raised portions of the bore,by first compressing the original sealing member beyond its elasticlimits by cold working it for partially orienting it by reducing itssection while in a crystalline state, further reducing the outerdiameter of said member by compression for introducing it into saidbore, and of further stressing said member to produce areas of greaterorientation by further reduction in section over the raised areas in thebore while simultaneously forcing other portions of the sleeve materialto partially fill the unraised areas of the bore for locking said memberin the bore.

Schenck Jan. 3, 1956 Freed Nov. 22, 1960

1. THE METHOD OF PROVIDING SELECTED AREAS OF IMPROVED SEALING PROPERTIESAND INCREASED RESISTANCE TO DEFORMATION UNDER COMPRESSIVE LOAD IN ANORIENTABLE, CRYSTALLINE SEALING MEMBER LOCATED BETWEEN A VALVING MEMBERAND THE BORE OF THE BODY OF A VALVE, WHEREIN THE BORE IS PROVIDED WITHCONTINUOUS RAISED AREAS WHICH CIRCUMSCRIBE THE BOREADJACENT-END OF FLOWPASSAGES INTHE BODY AND WITH RECESSED AREAS ADJACENT SAID RAISED AREAS;WHICH METHOD COMPRISES THE STEPS OF REDUCING THE DIAMETER OF THE SEALINGMEMBER INCIDENT TO INSERTING IT IN SAID BORE WHILE IN A CRYSTALLINESTATE, AND OF THEN COLD WORKING IT BY INVEASING ITS INTERNAL DIAMETERFOR COMPRESSING IT RADIALLY BEYOND ITS ELASTIC